With the advancement of technology, image display is no longer limited to screen plane of two-dimensional (2D) space, and three-dimensional (3D) picture display is applied more and more in people's daily work, study and entertainment.
In the real world, as shown in FIG. 1a, when normal eyes view an object O, the aggregation distance L of sight lines of two eyes equals to the focusing distance L′ of an individual eye, that is, both focusing positions are located on the viewed object O. However, in the present parallactic 3D world, as shown in FIG. 1b, since the screen provides only a binocular parallactic picture of the viewed light field but the respective light direction information required for single eye focusing, the focusing positions of individual eyes are always located at the screen while two eyes are converged to a virtual object outside of the screen due to the parallactic. That is, in the parallactic 3D world, the sight line aggregating distance L of two eyes does not equal to the focusing distance L′ of individual eyes, which in turn causes dizziness and discomfort while viewing 3D pictures with eyes.